Conventional wheelchairs include forward castor wheels generally of much smaller diameter than the principal side wheels of the chair itself. While the major portion of the weight of a patient is supported by the large side wheels of the wheelchair, some weight nevertheless is borne by the forward castor wheels. Because these wheels are of relatively smaller diameter than the main wheels, imperfections in the sidewalk or ground over which the wheelchair is riding such as in the form of cavities or ridges have a far greater effect than the larger wheels. Even such small imperfections as the cracks in a sidewalk can result in an annoying transmitting of shocks through the forward castor wheels to the entire wheelchair frame and over long periods of time, can become quite annoying to a patient.
The foregoing problem could be overcome if the castor wheels could be shock-mounted in some manner. While it is known to provide swivel type castor wheels with shock mounts in the form of coil springs and the like, for uses other than wheelchairs, to try to adapt such mountings as are known to wheelchairs would not only be awkward but would be unsightly in appearance and questionable in value. In this respect, it should be understood that adjacent to the forward castor wheels are the normal foot rests which in turn are mounted to the wheelchair frame proper in such a manner as to enable their being pivoted out-of-the-way or even removed from the wheelchair. Any type of shock absorbing mounting for the castor wheels must thus not interfere with normal operation of the footrests, which would mean that such mountings would have to be on the exterior sides of the wheels. In this latter event, the overall width of the wheelchair would be increased rendering it difficult to pass through narrow passageways.